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<!-- <body>记单词,一天记住五个单词，三天能记住多少个？ -->
<script>//循环天数
    for (let i = 1; i <= 3; i++) {

        document.write(`第${i}天<br>`)
        for (let num = 1; num <= 5; num++) {
            //一天所记的单词数
            document.write(`今天记了第${num}个单词<br>`)
        }

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